Expression of Rho Kinase and Its Mechanism in the Left Atrial Appendage in Patients with Atrial Fibrillation
Keywords:ROCK-1, MYPT-1, Cx40, Cx43, atrial fibrillation, LAA
Aim: To study the expression of Rho kinase (Rho associated coil forming protein kinase-1, ROCK-1) and its substrate myosin phosphatase target subunit 1 (myosin phosphatase target subunit-1, MYPT-1), connexin 40 (Cx40) and connexin 43 (Cx43) in the left atrial appendage of patients with atrial fibrillation, and explore the role of ROCK signaling pathway in patients with atrial fibrillation and its underlying mechanism.
Methods: 40 patients undergoing open heart surgery were divided into two groups; atrial fibrillation group (AF group) and sinus rhythm group (SR group). About 100 mg of left atrial appendage tissue was taken during surgery and quickly frozen in liquid nitrogen. Immunohistochemistry and western blot were performed to evaluate the expression and location of ROCK-1, MYPT-1, Cx40 and Cx43 in the left atrial appendage tissue.
Results: The results indicated that the expression of ROCK-1, MYPT-1, and Cx40 in the left atrial appendage in patients with atrial fibrillation was significantly upregulated (P < .01), the difference in the two groups was statistically significant, and ROCK-1, Cx40, and MYPT-1 expression in the AF group were higher than those in sinus rhythm group; there was a weakly positive expression of Cx43 protein in the AF group and sinus rhythm group, the difference was not statistically significant, and ROCK-1 and MYPT-1 expression showed a significant positive correlation (r = 0.968,
P < .05), MYPT 1 and Cx40 protein expression was also positively correlated (r = 0.983, P < .05). Evidence in the left atrial appendage tissue of patients with atrial fibrillation showed that some proteins in Rho/ROCK pathway were upregulated, and MYPT-1 and Cx40 protein expression in AF group were significantly higher than that of SR group, which was also positively correlated; Cx43 showed a weak positive expression in both the SR group and AF group, which indicates that Rho kinase may induce expression of Cx40 by phosphorylation of MYPT-1; Cx43 may not be involved, suggesting that Rho kinase signaling pathway may activate and play an important role in the pathogenesis of atrial fibrillation lesions.
Chapados R, Abe K, Ihida-Stansbury K, et al. 2006. ROCK controls matrix synthesis in vascular smooth muscle cells: coupling vasoconstriction to vascular remodeling. Circ Res 99:837-44.
Dupays L, Mazurais D, Rücker-Martin C, et al. 2003. Genomic organization and alternative transcripts of the human Connexin40 gene. Gene 305:79-90.
Furuyama T, Komori K, Shimokawa H, et al. 2006. Long-term inhibition of Rho kinase suppresses intimal thickening in autologous vein grafts in rabbits. J Vasc Surg 43:1249-56.
Higashi M, Shimokawa H, Hattori T, et al. 2003. Long-term inhibition of Rho-kinase suppresses angiotensin II-induced cardiovascular hypertrophy in rats in vivo: effect on endothelial NAD(P)H oxidase system. Circ Res 93:767-75.
Ishizaki T, Naito M, Fujisawa K, et al. 1997. p160ROCK, a Rho-associated coiled-coil forming protein kinase, works downstream of Rho and induces focal adhesions. FEBS Lett 404:118-24.
Ito K, Hirooka Y, Kishi T, et al. 2004. Rho/Rho-kinase pathway in the brainstem contributes to hypertension caused by chronic nitric oxide synthase inhibition. Hypertension 43:156-62.
Jansen JA, van Veen TA, de Bakker JM, et al. 2010. Cardiac connexins and impulse propagation. J Mol Cell Cardiol 48:76-82.
Kandabashi T. 2000. Inhibition of myosin phosphatase by upregulated rho-kinase plays a key role for coronary artery spasm in a porcine model with interleukin-1beta. Circulation 101:1319-23.
Kandabashi T, Shimokawa H, Mukai Y, et al. 2002. Involvement of rho-kinase in agonists-induced contractions of arteriosclerotic human arteries. Arterioscler Thromb Vasc Biol 22:243-8.
Kimura K, Ito M, Amano M, et al. 1996. Regulation of myosin phosphatase by Rho and Rho-associated kinase (Rho-kinase). Science 273:245-8.
Loirand G, Guerin P, Pacaud P. 2006. Rho kinases in cardiovascular physiology and pathophysiology. Circ Res 98:322-34.
Mam V, Tanbe AF, Vitali SH, et al. 2010. Impaired vasoconstriction and nitric oxide-mediated relaxation in pulmonary arteries of hypoxia- and monocrotaline-induced pulmonary hypertensive rats. J Pharmacol Exp Ther 332:455-6.
Narumiya S. 1996. The small GTPase Rho: cellular functions and signal transduction. J Biochem 120:215-28.
Noma K, Oyama N, Liao JK. 2006. Physiological role of ROCKs in the cardiovascular system. Am J Physiol Cell Physiol 290:C661-8.
Nossaman BD, Nossaman VE, Murthy SN, et al. 2010. Role of the RhoA/Rho-kinase pathway in the regulation of pulmonary vasoconstrictor function. Can J Physiol Pharmacol 88:1-8.
Pellman J, Lyon RC, Sheikh F. 2010. Extracellular matrix remodeling in atrial fibrosis: mechanisms and implications in atrial fibrillation. J Mol Cell Cardiol 48:461-7.
Rackauskas M, Neverauskas V, Skeberdis VA. 2010. Diversity and properties of connexin gap junction channels. Medicina (Kaunas) 46:1-12.
Severs NJ, Coppen SR, Dupont E, et al. 2004. Gap junction alterations in human cardiac disease. Cardiovasc Res 62:368-77.
Shatanawi A, Romero MJ, Iddings JA, et al. 2011. Angiotensin II-induced vascular endothelial dysfunction through RhoA/Rho kinase/p38 mitogen-activated protein kinase/arginase pathway. Am J Physiol Cell Physiol 300: C1181-92.
Shimokawa H, Takeshita A. 2005. Rho-kinase is an important therapeutic target in cardiovascular medicine. Arterioscler Thromb Vasc Biol 25:1767-75.
Uehata M, Ishizaki T, Satoh H, et al. 1997. Calcium sensitization of smooth muscle mediated by a Rho-associated protein kinase in hypertension. Nature 389:990-4.
Wang N, Guan P, Zhang JP, et al. 2010. Fasudil hydrochloride hydrate, a Rho-kinase inhibitor, suppresses isoproterenol-induced heart failure in rats via JNK and ERK1/2 pathways. J Cell Biochem 112:1920-9.
Wettschureck N, Offermanns S. 2002. Rho/Rho-kinase mediated signaling in physiology and pathophysiology. J Mol Med (Berl) 80:629-38.
Zhou Q, Gensch C, Liao JK. 2011. Rho-associated coiled-coil-forming kinases (ROCKs): potential targets for the treatment of atherosclerosis and vascular disease. Trends Pharmacol Sci 32:167-73.
How to Cite
Author Disclosure & Copyright Transfer Agreement
In order to publish the original work of another person(s), The Heart Surgery Forum® must receive an acknowledgment of the Author Agreement and Copyright Transfer Statement transferring to Forum Multimedia Publishing, L.L.C., a subsidiary of Carden Jennings Publishing Co., Ltd. the exclusive rights to print and distribute the author(s) work in all media forms. Failure to check Copyright Transfer agreement box below will delay publication of the manuscript.
A current form follows:
The author(s) hereby transfer(s), assign(s), or otherwise convey(s) all copyright ownership of the manuscript submitted to Forum Multimedia Publishing, LLC (Publisher). The copyright transfer covers the exclusive rights to reproduce and distribute the article and the material contained therein throughout the world in all languages and in all media of expression now known or later developed, including but not limited to reprints, photographic reproduction, microfilm, electronic data processing (including programming, storage, and transmission to other electronic data record(s), or any other reproductions of similar nature), and translations.
However, Publisher grants back to the author(s) the following:
- The right to make and distribute copies of all or part of this work for use of the author(s) in teaching;
- The right to use, after publication in The Heart Surgery Forum, all or part of the material from this work in a book by the author(s), or in a collection of work by the author(s);
- The royalty-free right to make copies of this work for internal distribution within the institution/company that employs the author(s) subject to the provisions below for a work-made-for-hire;
- The right to use figures and tables from this work, and up to 250 words of text, for any purpose;
- The right to make oral presentations of material from this work.
Publisher reserves the right to grant or refuse permission to third parties to republish all or part of the article or translations thereof. To republish, such third parties must obtain written permission from the Publisher. (This is in accordance with the Copyright Statute, United States Code, Title 17. Exception: If all authors were bona fide officers or employees of the U.S. Government at the time the paper was prepared, the work is a “work of the US Government” (prepared by an officer or employee of the US Government as part of official duties), and therefore is not subject to US copyright; such exception should be indicated on signature lines. If this work was prepared under US Government contract or grant, the US Government may reproduce, royalty-free, all or portions of this work and may authorize others to do so, for official US Government purposes only, if the US Government contract or grant so requires.
I have participated in the conception and design of this work and in the writing of the manuscript and take public responsibility for it. Neither this manuscript nor one with substantially similar content under my authorship has been published, has been submitted for publication elsewhere, or will be submitted for publication elsewhere while under consideration by The Heart Surgery Forum, except as described in an attachment. I have reviewed this manuscript (original version) and approve its submission. If I am listed above as corresponding author, I will provide all authors with information regarding this manuscript and will obtain their approval before submitting any revision. I attest to the validity, accuracy, and legitimacy of the content of the manuscript and understand that Publisher assumes no responsibility for the validity, accuracy, and legitimacy of its content. I warrant that this manuscript is original with me and that I have full power to make this Agreement. I warrant that it contains no matter that is libelous or otherwise unlawful or that invades individual privacy or infringes any copyright or other proprietary right. I agree to indemnify and hold Publisher harmless of and from any claim made against Publisher that relates to or arises out of the publication of the manuscript and agree that this indemnification shall include payment of all costs and expenses relating to the defense of any such claim, including all reasonable attorney’s fees.
I warrant that I have no financial interest in the drugs, devices, or procedures described in the manuscript (except as disclosed in the attached statement).
I state that the institutional Human Subjects Committee and/or the Ethics Committee approved the clinical protocol reported in this manuscript for the use of experimental techniques, drugs, or devices in human subjects and appropriate informed consent documents were utilized.
Furthermore, I state that any and all animals used for experimental purposes received humane care in USDA registered facilities in compliance with the “Principles of Laboratory Animal Care” formulated by the National Society for Medical Research and the “Guide for the Care and Use of Laboratory Animals” prepared by the Institute of Laboratory Animal Resources and published by the National Institutes of Health (NIH Publication No. 85-23, revised 1985).